Injection molding processes are well known, and generally involve injecting a flowable material such as a plastic into a cavity prepared in a mold, and allowing the material to cool and harden to form a product that has a form generally complementary to that of the mold cavity.
In a variation of such processes, a film may be integrally formed on the product by inserting the film or substrate into the mold prior to the injection of the molten material.
US2005/140055 discloses a method for making a part by injection molding and decorating a visually-exposed face surface and a visually-exposed side surface of the part in their entireties during the injection molding of the part. The method includes the steps of providing a mold, inserting a decorative film into the mold, closing the mold, injecting a molten material into the mold causing the decorative film to conform to the mold by virtue of the molten material, when filling the mold, exerting a force on the decorative film forcing the decorative film to abut intimately against the mold, hardening the molten material so as to form a hardened core, and forming the part with the decorative film being adhered to the hardened core, by virtue of the decorative film being possessed by the hardened core when the molten material hardens and becomes the hardened core, so as to allow the decorative film to cover the hardened core and thereby eliminate a concern for color inconsistency of the hardened core caused by color variations of the molten material by virtue of the hardened core being covered by the decorative film.
U.S. 2003/0122278 discloses a method for applying multiple decorative sheets of film to an injection-mold component as a part of the injection mold process. Two sheets of film having desired images are permanently affixed to the surfaces of the injection mold component as a part of the injection molding process. An enhanced three-dimensional appearance is achieved by affixing the images to a transparent injection mold component.
U.S. Pat. No. 4,052,497 discloses a method for the manufacture by injection molding of articles composed of a plurality of layers of at least three distinct materials coated one over the other. The method includes the steps of successive injection of a measured quantity of a first material adapted to form the skin of the article, a measured quantity of a second material to form the intermediate layer, and a measured quantity of a third material to form the body of the article. The materials are introduced into the mold coaxially so as to give a uniform distribution. The method is especially applicable to the production of articles in which the external and internal materials are joined together by an intermediate material.
U.S. Pat. No. 4,686,076 discloses a method, machine, and mold for fabricating, by injection of synthetic material, containers having a film forming an external coating. The machine includes a mold, an injection nozzle, a film feed device, and apparatus for holding the film against the male element of the mold. The injection nozzle is carried by the male element of the mold and the holding apparatus includes a slider in the cavity of the female element movable, under the action of the male element, against a return force.
U.S. Pat. No. 5,240,751 discloses a decorative automotive vehicle trim strip and method and apparatus for forming by reshaping an end of a previously extruded length of thermoplastic material. The surface of the length of the thermoplastic material intended for viewing is maintained at a cold temperature, well below the softening point of the thermoplastic material, during the reshaping operation. The length of the thermoplastic material is heated during reshaping by a mold section heated to 400 degrees F. to 410 degrees F. pressed against the surface intended to be affixed to the vehicle.
U.S. Pat. No. 5,415,536 discloses a method for forming a pattern onto an article during injection molding thereof. A pattern-bearing film is heated and softened by a heating board. The softened pattern-bearing film is transferred to the cavity surface of a female mold. Thereafter, the female mold and a male mold are closed. Then, a molten resin is injected into the cavity. When the pattern-bearing film is brought into contact with and heated by the heating board, marks or impressions of air blow holes on the surface of the heating board remain on the pattern-bearing film. To prevent the formation of these marks or impressions, a square-shaped holding frame is fixed on the surface of the heating board. The peripheral portion of the pattern-bearing film is held on the surface of the holding frame. Thus, while the pattern portion of the pattern-bearing film is spaced apart from the surface of the heating board, the film is heated. To keep the pattern-bearing film uniformly spaced from the surface of the heating board, air is supplied to the inside of the holding frame.
U.S. Pat. No. 6,090,336 discloses a method and apparatus for manufacturing an injection-molded article having an outer film on an exposed surface. The method includes securing the film about its periphery within a mold cavity prior to injection of molten material into the cavity. One way of securing the film is by applying vacuum pressure through peripheral holes in a frame surrounding the mold cavity. Molten material is injected into the cavity behind the film, and the film slips from its initial position to be forced against a wall of the cavity by molten material being injected into the cavity. The apparatus includes a frame for a molding apparatus adapted to initially secure the film in place prior to movement of the core block into place and to permit the film to slip from its initial position to be forced against the cavity wall as molten material fills the cavity.
U.S. Pat. No. 6,474,976 discloses a film holding apparatus for an injection mold which is capable of surely holding a protective film on a specific position of a mold surface of the injection mold. The film holding apparatus for holding an inner film on the mold surface of the injection molds consisting of two coupled molds having substantially-vertical coupled surfaces thereof which includes two positioning pins that can hang an upper edge side of the inner film on an upper edge portion of the mold surface of the mold, and upper and lower vacuum opening portions for film adsorption disposed so as to interpose the positioning pins therebetween from the upper and lower sides. The upper vacuum opening portion is formed in a line which extends along an upper edge of the mold surface.